Figure 2.
The fabricated 4 × 4 SnO 2 gas sensor array with the structure of an individual sensor highlighted on the right. There are 16 SnO2 sensors, corresponding to different combinations of dopants and catalysts. Sensors belonging to the same column share the same metal catalyst (Pt, Ag, or Au), while row wise sensors share the same dopant (B, P, or H). A single row has no dopant (ND) and a single column has no metal catalyst (NC). Note that the above sensor numbering is kept for all subsequent figures.